The invention relates to an arrangement for achieving efficient cooling of the hydraulic fluid in a hydraulic-powered vibrating compactor.
1. Background of the Invention
With a hydraulic drive, heat is generated in the hydraulic system due to pressure losses. Known arrangements for cooling the hydraulic fluid of the system include a sufficiently large hydraulic fluid reservoir or a conventional oil cooler. However, small compactors in particular preclude the first of these solutions because an oil cooler is both bulky and expensive.
2. Summary of the Invention
It is an object of the invention to provide a hydraulic-powered vibrating compactor with efficient cooling of the hydraulic fluid in a simple and cost effective manner.
The arrangement of the invention is for cooling hydraulic fluid in a hydraulic-powered vibrating compactor and includes a chassis, a casing mounted on the chassis and a reservoir defining an interior for the hydraulic fluid. The arrangement includes: the reservoir being disposed below the casing and having a lower wall defining a tunnel and an upper wall in spaced relationship to the casing so as to define a passage communicating with the atmosphere external of the casing; the lower wall and the upper wall enclosing at least a portion of the interior; a hydraulic pump connected to the chassis and having a through rotatable shaft defining a free end; a fan wheel mounted on the free end; the hydraulic pump being mounted so as to permit the fan wheel to draw cooling air through the tunnel for cooling the hydraulic fluid in the reservoir; and, means for directing the cooling air from the tunnel and into the passage so as to permit the cooling air to pass over the upper wall to further cool the hydraulic fluid in the reservoir and to discharge to the atmosphere outside of the casing.
The arrangement of the invention is especially advantageous because the feasibility of using conventional cooling methods is limited by the size of the machine.
Another purpose of the invention is to permit the use of environmentally compatible biofluids which, as is known, cannot withstand high temperatures. This is achieved by configuring the fluid reservoir in the shape of a tunnel and providing the hydraulic pump with a through shaft having a fan wheel mounted on one end. Installed in the duct formed by the tunnel-shaped reservoir, the fan wheel generates a flow of cooling air in the duct and this flow is directed further along the top of the reservoir by a baffle plate. Practical tests using this arrangement have shown that the fluid temperature is reduced by approximately 30xc2x0 C. and that an operating temperature of approximately 50xc2x0 C. above ambient is achieved thereby enabling biofluids to also be used.